Faculdade de Ciencias da Universidade de Lisboa 2 articles published in JoVE Developmental Biology Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation André Dias1, Gabriel G. Martins1,2, Alexandre Lopes1,3, Moisés Mallo1 1Instituto Gulbenkian de Ciência, 2Faculdade de Ciências da Universidade de Lisboa, 3NOVA School of Science and Technology Here, we describe computational tools and methods that allow visualization and analysis of three and four-dimensional image data of mouse embryos in the context of axial elongation and segmentation, obtained by in toto optical projection tomography, and by live imaging and whole-mount immunofluorescence staining using multiphoton microscopy. Environment BtM, a Low-cost Open-source Datalogger to Estimate the Water Content of Nonvascular Cryptogams María Leo*1, Angel Lareo*2, Carlos Garcia-Saura2, Joaquín Hortal3,4, Nagore G. Medina5 1Real Jardín Botánico (CSIC-RJB), 2Grupo de Neurocomputación Biológica, Dpto. de Ingeniería Informática, Escuela Politécnica Superior, Universidad Autónoma de Madrid, 3Department of Biogeography and Global Change, Museo Nacional de Ciencias Naturales (MNCN-CSIC), 4Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências da Universidade de Lisboa, 5Department of Botany, Faculty of Science, University of South Bohemia We present a simple and cost-effective method to build an open-source datalogger that measures the conductance of nonvascular cryptogams together with the environmental temperature and humidity. We describe the hardware design of the datalogger and provide step-by-step assembly instructions, the list of required open-source logging software, the code to run the datalogger, and a calibration protocol.